When silicon dots or nanoclusters are formed in a data storage portion of an integrated circuit, the nanoclusters that are deposited in peripheral regions have to be removed prior to the formation of peripheral devices. During deposition nanoclusters of differing sizes and shapes are formed. Some deposited nanoclusters are much larger than others while others are oblong in shape. The deposition of nanoclusters is not selective across a semiconductor substrate and thus nanoclusters must be selectively removed after the deposition. The presence of random size distributions of nanoclusters is problematic as some nanoclusters are typically left in place when conventional etching processes are used. Even with tight nanocluster processing control that results in a narrow dispersion of cluster sizes, the presence of a few substantially larger clusters in the peripheral area is not statistically insignificant. When nanoclusters are deposited on a thin oxide surface, a long wet etch or dry etch is required to remove those nanoclusters which are substantially larger than the mean size. Such a long wet etch or a dry etch will often compromise the integrity of devices built in the peripheral areas. For example, such etches will unintentionally remove portions of layers in the peripheral areas which are not desired or intended to be removed. A typical example is the recess of the trench isolation oxide and its concomitant problems. A long wet etch or dry etch therefore compromises the integrity of devices built in the peripheral areas. Selective removal of nanoclusters is therefore problematic.
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